The present invention relates to a carton formed from foldable sheet material, such as paperboard, primarily for use in packaging food products, particularly for the fast food industry.
The manufacture of food cartons, particularly for the fast food industry, involves highly developed technology. Such cartons must be designed for maximum economy and utility with emphasis on ease of use, cost effectiveness, handling, filling, and closing. Product identification, storage of cartons for end use, and integrity after being filled are also important. When such cartons are to be used for hot foods, design considerations must be incorporated into the carton structure to provide a quick and easy means for loading and closing the carton to keep the food hot, and for retaining the lids closed until the food is to be served. Conversely, the means for keeping the lids closed must be readily releasible by the consumer when the foods are to be consumed. Preferably, the means for keeping the lids closed should be automatically engaged upon closing, and easily released when desired.
Likewise, it is desirable in such cartons to provide a means for stacking a plurality of cartons, one on top of the other, for carryout use. When stacked, the cartons should include some mechanism for retaining the plurality of cartons in a stack. Likewise, it is useful and desirable to provide a readily accessible carry handle for ease of carrying one or more filled cartons. However, even though a clear need has existed in the fast food industry for a carryout carton with an effective, positive, automatic closure, good stacking ability and the bonus of providing a readily available carry handle, no such package exists in the prior art. Thus, while U.S. Pat. No. 3,529,763 discloses a typical automatic bottom as employed in the present invention, and U.S. Pat. No. 4,516,718 discloses a type of front locking closure that is related to the design used herein, it has not been obvious to the prior workers in the field to design a single carton which satisfies all of the above desirable features substantially as disclosed herein.